Mega Magz, 130-Piece Magnetic Construction Set - 66 bars and 64 balls MegaMagz is a safe, creative and fun magnetic building system consisting of 66 magnetic bars (2.3" long) and 64 steel balls (0.5" diameter). MegaMagz comes in a luxury wooden storage box in cherry color. It is fun and easy to play. You become an instant builder and creator. All ages over 3 years can enjoy MegaMagz. MegaMagz is tested for all required ASTM and CPSC standards. It is SAFE! Collect more pieces and build larger. You can build towers and high rises with MegaMagz.